DOC: Code on Pages 75-76 of Developer's Guide Causes Error (139110)

SUMMARY

When you use the code example listed on pages 75-76 of the Developer's Guide, the following error occurs:

Error with <ObjectName>- Height: Expression evaluated to an illegal value

This documentation error has been fixed in Visual FoxPro 5.0 for Windows.

MORE INFORMATION

The error occurs because 12 is not a valid size for the Height property of the object when the ScaleMode property is set to 3 (Pixels). The default ScaleMode property of the form is set to Pixels, and the object is designed to use Foxels, even though there is a line in the DEFINE CLASS grdProducts AS Grid stating:

   ScaleMode = 0

The ScaleMode property is a property of the form, not the grid.

To use the code example, make these two changes:

Move the ScaleMode property into the code for the DEFINE CLASS GridForm AS FORM.
Place "Height = 12" in the PROCEDURE INIT of the grid.

By the time the grid is to be shown, the form's ScaleMode property will now be set to 0 (Foxels). After you make the two changes, the code from the Developer's Guide should look like this:

   DEFINE CLASS GridForm AS FORM
       ScaleMode = 0
       <other statements>
   ENDDEFINE

   DEFINE CLASS grdProducts AS Grid
    <other statements>

     PROCEDURE INIT
       This.Height = 12
     ENDPROC

   ENDDEFINE